DataTable迭代可提供不需要的数据 [英] DataTable iteration gives unwanted data

问题描述

我正在使用SqlDataAdapter遍历DataTable并将其存储在列表中。
这是我的代码。

I am iterating through a DataTable using SqlDataAdapter and storing it in a list. Here is my code.

public IEnumerable<DataRow> GetRecord()
{
    var table = new DataTable();
    using (var da = new SqlDataAdapter("SELECT * FROM mv_tbl", "ConnectionString"))
    {
        da.Fill(table);
        List<DataRow> list = new List<DataRow>();
        foreach (DataRow r in table.Rows)
        {
            list.Add(r);
        }

        return list;
    }
}

这给了我一个也有不必要数据的结果。结果如下。

This gives me a result which has unnecessary data also. Here is the result.

[{"RowError":"",
"RowState":2,
"Table":[{"mv_id":2,
"mv_name":"Up",
"mv_link":"link",
"user":"[e-mail]",
"db_tstamp":"2020-01-01T01:50:00"},
{"mv_id":3,
"mv_name":"8 Below",
"mv_link":"link",
"user":"[e-mail]",
"db_tstamp":"2020-01-01T02:49:00"}],
"ItemArray":[2,"Up","link","[e-mail]","2020-01-01T01:50:00"],
"HasErrors":false},
{"RowError":"",
"RowState":2,
"Table":[{"mv_id":2,
"mv_name":"Up",
"mv_link":"link",
"user":"[e-mail]",
"db_tstamp":"2020-01-01T01:50:00"},
{"mv_id":3,
"mv_name":"8 Below",
"mv_link":"link",
"user":"[e-mail]",
"db_tstamp":"2020-01-01T02:49:00"}],
"ItemArray":[3,"8 Below","link","[e-mail]","2020-01-01T02:49:00"],
"HasErrors":false}]

我的预期结果是。

[{"mv_id":2,
    "mv_name":"Up",
    "mv_link":"link",
    "user":"[e-mail]",
    "db_tstamp":"2020-01-01T01:50:00"},
    {"mv_id":3,
    "mv_name":"8 Below",
    "mv_link":"link",
    "user":"[e-mail]",
    "db_tstamp":"2020-01-01T02:49:00"}]

这是数据库中的屏幕截图。

Here is a screenshot from the database.

我的原始问题在这里。

如何返回动态表的行列表？

我在哪里弄错了？？

推荐答案

您可以将 DataTable 转换为 Dictionary< string，object> （ EnumerableRowCollection<字典< string，object> ）

var result = dt.AsEnumerable()
                    .Select(row => dt.Columns
                                     .Cast<DataColumn>()
                                     .ToDictionary(column => column.ColumnName,column => row[column]));
return result;

这也会从Web API产生所需的Json返回。

This would also produce the desired Json return from Web API.

或者，您可以返回 DataTable 本身，也可以使用匿名类型或用户定义的类的集合。

Alternatively, you could return the DataTable itself or make use of collection of anonymous types or user defined class.

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